1,573 research outputs found

    Loss of Function in Escherichia coli exposed to Environmentally Relevant Concentrations of Benzalkonium Chloride

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    Assessing the risk of resistance associated with biocide exposure commonly involves exposing microorganisms to biocides at concentrations close to the MIC. With the aim of representing exposure to environmental biocide residues, MG1655 was grown for 20 passages in the presence or absence of benzalkonium chloride (BAC) at 100 ng/L and 1000 ng/L (0.0002% and 0.002% of the MIC respectively). BAC susceptibility, planktonic growth rates, motility and biofilm-formation were assessed, and differentially expressed genes determined via RNA-sequencing. Planktonic growth rate and biofilm-formation were significantly reduced (p<0.001) following BAC adaptation, whilst BAC minimum bactericidal concentration increased two-fold. Transcriptomic analysis identified 289 upregulated and 391 downregulated genes after long-term BAC adaptation when compared to the respective control organism passaged in BAC-free-media. When the BAC-adapted bacterium was grown in biocide-free medium, 1052 genes were upregulated and 753 were down regulated. Repeated passage solely in biocide-free medium resulted in 460 upregulated and 476 downregulated genes compared to unexposed bacteria. Long-term exposure to environmentally relevant BAC concentrations increased the expression of genes associated with efflux and reduced gene expression associated with outer-membrane porins, motility and chemotaxis. This was manifested phenotypically through loss-of-function (motility). Repeated passage in a BAC-free-environment resulted in the up-regulation of multiple respiration-associated genes, which was reflected by increased growth rate. In summary, repeated exposure of to BAC residues resulted in significant alterations in global gene expression that were associated with minor decreases in biocide susceptibility, reductions in growth-rate and biofilm-formation, and loss of motility. Exposure to very low concentrations of biocide in the environment is a poorly understood risk factor for antimicrobial resistance. Repeated exposure to trace levels of the biocide BAC resulted in loss of function (motility) and a general reduction in bacterial fitness, but relatively minor decreases in susceptibility. These changes were accompanied by widespread changes in the transcriptome. This demonstrates the importance of including phenotypic characterisation in studies designed to assess the risks of biocide exposure. [Abstract copyright: Copyright © 2018 American Society for Microbiology.

    Supporting activity engagement by family carers at home: maintenance of agency and personhood in dementia

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    Objective: An explorative paper to describe how family carers, through the caregiving journey, reaffirm and promote the agency of people with dementia. Agency is an important concept in dementia care; and is crucial to the promotion of wellbeing and the delivery of person-centred care. This article is based on one of the key findings of a study that explored family carers’ experiences of engaging their relatives in daily activities in domestic settings. Method: Following research governance and ethical approval, 30 in-depth interviews (initial and follow-up) were carried out with 15 resident-carers of people with dementia who were recruited via local community mental health teams. Then five focus groups were conducted with 21 participants accessed through carers support groups. Interviews and focus groups were transcribed, coded and analysed using a grounded theory method. Results: Findings showed the process in which family carers encouraged and sustained a sense of autonomy and control (agency) in their relative’s daily activities. Key strategies used by carers included: being non-judgemental; facilitating a sense of worth; taking calculated risks; maintaining the continuity of their relative’s identity; enhancing a sense of connection with their relative’s role and identity, using enjoyable activities; preventing inactivity and attending to the bodily source of the agency. Lack of support for carers could ultimately pose a risk to the maintenance of the agency of people with dementia. Conclusion: This study provides a deeper insight into the process used by home carers to support the agency of people with dementia. This is essential if practitioners are to identify and develop more realistic intervention strategies and to work in effective partnership with family carers. The implications for the creation of dementia-friendly communities are discussed

    A comparison of the illness beliefs of people with angina and their peers: a questionnaire study

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    BACKGROUND: What people believe about their illness may affect how they cope with it. It has been suggested that such beliefs stem from those commonly held within society . This study compared the beliefs held by people with angina, regarding causation and coping in angina, with the beliefs of their friends who do not suffer from angina. METHODS: Postal survey using the York Angina Beliefs Questionnaire (version 1), which elicits stress attributions and misconceived beliefs about causation and coping. This was administered to 164 people with angina and their non-cohabiting friends matched for age and sex. 132 people with angina and 94 friends completed the questionnaire. RESULTS: Peers are more likely than people with angina to believe that angina is caused by a worn out heart (p <0.01), angina is a small heart attack (p = 0.02), and that it causes permanent damage to the heart (p <0.001). Peers were also more likely to believe that people with angina should take life easy (p <0.01) and avoid exercise (p = 0.04) and excitement (p <0.01). CONCLUSIONS: The beliefs of the peer group about causation and coping in angina run counter to professional advice. Over time this may contribute to a reduction in patient concordance with risk factor reduction, and may help to create cardiac invalids

    HRS/EHRA/ECAS expert consensus statement on catheter and surgical ablation of atrial fibrillation: Recommendations for personnel, policy, procedures and follow-up. A report of the Heart Rhythm Society (HRS) Task Force on catheter and surgical ablation of atrial fibrillation

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    During the past decade, catheter ablation of atrial fibrillation (AF) has evolved rapidly from a highly experimental unproven procedure, to its current status as a commonly performed ablation procedure in many major hospitals throughout the world. Surgical ablation of AF, using either standard or minimally invasive techniques, is also performed in many major hospitals throughout the world. The purpose of this Consensus Statement is to provide a state-of-the-art review of the field of catheter and surgical ablation of AF, and to report the findings of a Task Force, convened by the Heart Rhythm Society and charged with defining the indications, techniques, and outcomes of this procedure. The Heart Rhythm Society was pleased to develop this Consensus Statement in partnership with the European Heart Rhythm Association and the European Cardiac Arrhythmia Society. This statement summarizes the opinion of the Task Force members based on their own experience in treating patients, as well as a review of the literature, and is directed to all health care professionals who are involved in the care of patients with AF, particularly those who are undergoing or are being considered for catheter or surgical ablation procedures for AF. This statement is not intended to recommend or promote catheter ablation of AF. Rather the ultimate judgment regarding care of a particular patient must be made by the health care provider and patient in light of all the circumstances presented by that patient. In writing a "consensus" document, it is recognized that consensus does not mean that there was complete agreement among all Task Force members. We attempted to identify those aspects of AF ablation for which a true "consensus" could be identified ( Tables 1 and 2 ). Surveys of the entire Task Force were used to identify these areas of consensus. The main objective of this document is

    The promises of genomic screening: building a governance infrastructure. Special issue: genetics and democracy

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    New screening possibilities become available at a high rate, both useful and unsound possibilities. All screening programmes do harm, and only few have more advantages than disadvantages at reasonable cost. Horizon scanning is needed to identify those few possibilities with more pros than cons. Attunement is needed between actors involved: scientists developing new high-throughput screening techniques and treatment, health care workers, patients and consumers and governmental agencies. The product of a process of attunement may be a quality mark as a norm for professional conduct, rather than legal measures, as the field is moving fast. As actors may have varying perspectives, a governance structure is needed to develop an agenda that is agreed upon by all or most actors involved. A standing committee might oversee the evaluation of benefits and disadvantages in an integrated approach, taking evidence, economics and ethics into account. A proactive role of governmental agencies is needed to facilitate agenda setting and attunement. Policy making has to be transparent and open to stakeholder engagement

    Sex differences and heritability of two indices of heart rate dynamics: A twin study.

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    We investigated whether women show larger heart rate variability (HRV) than men after controlling for a large number of health-related covariates, using two indices of HRV, namely respiratory sinus arrhythmia (RSA) and approximate entropy (ApEn). In a twin design, the heritability of both indices was examined. The covariation between RSA and ApEn, a measure of heart rate dynamics derived from nonlinear dynamical systems theory, was decomposed into genetic and environmental components. Subjects were 196 male and 210 female middle-aged twins. Females showed larger HRV than men before (ApEn: p <.001; RSA: p = .052) and after adjustment for covariates (ApEn: p <.001; RSA: p = .015). This sex difference was confirmed by significant intrapair differences in the opposite-sex twin pairs for both ApEn (p <.001) and RSA (p = .03). In addition to sex, only heart period and age (both p <.001) were found to be independent predictors of ApEn, whereas RSA was also influenced by respiration rate and smoking (both p <.001). Age explained 16% and 6% of the variance in FSA and ApEn, respectively. Oral contraceptive use and menopausal status had no effect on HRV. Genetic model fitting yielded moderate heritability estimates for RSA (30%) and ApEn (40%) for both males and females. The correlation between RSA and ApEn (r = .60) could be attributed to genetic factors (48%), environmental factors (36%) and age (16%). The present study found support for a gender difference in HRV with women having greater HRV than men even after controlling for a large number of potential confounders. Indices of heart rate dynamics derived from nonlinear dynamical systems theory are moderately heritable and may be more sensitive than traditional indices of HRV to reveal subtle sex differences with important implications for health and disease

    General practitioners' reasoning when considering the diagnosis heart failure: a think-aloud study

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    BACKGROUND: Diagnosing chronic heart failure is difficult, especially in mild cases or early in the course of the disease, and guidelines are not easily implemented in everyday practice. The aim of this study was to investigate general practitioners' diagnostic reasoning about patients with suspected chronic heart failure in comparison with recommendations in European guidelines. METHODS: Think-aloud technique was used. Fifteen general practitioners reasoned about six case vignettes, representing authentic patients with suspected chronic heart failure. Information about each case was added successively in five steps. The general practitioners said their thoughts aloud while reasoning about the probability of the patient having chronic heart failure, and tried to decide about the diagnosis. Arguments for and against chronic heart failure were analysed and compared to recommendations in guidelines. RESULTS: Information about ejection fraction was the most frequent diagnostic argument, followed by information about cardiac enlargement or pulmonary congestion on chest X-ray. However, in a third of the judgement situations, no information about echocardiography was utilized in the general practitioners' diagnostic reasoning. Only three of the 15 doctors used information about a normal electrocardiography as an argument against chronic heart failure. Information about other cardio-vascular diseases was frequently used as a diagnostic argument. CONCLUSIONS: The clinical information was not utilized to the extent recommended in guidelines. Some implications of our study are that 1) general practitioners need more information about how to utilize echocardiography when diagnosing chronic heart failure, 2) guidelines ought to give more importance to information about other cardio-vascular diseases in the diagnostic reasoning, and 3) guidelines ought to treat the topic of diastolic heart failure in a clearer way
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